VICKREY’S TWELVE PRINCIPLES FOR EFFICIENT CONGESTION PRICING (1992)
Brief summary of Prof. William S. Vickrey’s "Principles for Efficient Congestion Pricing." A longer version may be found at http://tinyurl.com/277uxc
Charges should equal or exceed the marginal social cost of each trip.
Charges should vary in sufficiently small increment to avoid creating mini-peaks.
Marginal social cost should be determined by the amount of time a vehicle is in the congestion queue. A vehicle arriving early in a congestion queue causes more congestion than one arriving late.
Charges are optimally based on trip segments rather than passage beyond a point.
Charges are optimally based on actual congestion rather than a predetermined schedule. Ideally drivers could be warned to stay away from certain areas where accidents had occurred and would be penalized for ignoring the warning.
All vehicles should be charged including trucks, emergency and media vehicles, and the vehicles of “public officials and diplomats.” The City should be aware, “even if this is only an accounting transfer,” of the congestion it causes.
Taxicabs should be charged and the charge should appear on the meter so that the passenger pays.
On-street parking spaces should be charged for based on the percentage of spaces on the block that are occupied. If 5 percent or fewer spaces are vacant, the charge should be high. If 20 percent or more spaces are vacant, the charge should decline to little or nothing.
Parking charges could be assessed by assigning each vehicle an account or card.
Or parking charges could be assessed using parking ticket vending machines, which will display an hourly charged based on the percentage of spaces that are vacant, which can be computed by the machine.
Delivery vehicles require loading bays and a system that imposes extra charges when they double-park.
The majority of the population that benefits from congestion pricing – and will see faster buses and emergency vehicles – should support it strongly to offset those who feel they lose the most.